Welding machine



FIG. 1 is an enlarged perspective view of a welding machine showing my new design;

FIG. 2 is a top plan view thereof, the bottom being unornamented;

FIG. 3 is a front elevational view thereof;

FIG. 4 is a side elevational view taken from the right of FIG. 1, the side opposite being a mirror image thereof;

FIG. 5 is a rear elevational view thereof. 

The ornamental design for a welding machine, as shown and described. 